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F = ma (Final Problems)
Simple Harmonic Motion
FMA-2020A-24 · 2020A F = ma (AAPT)

2020 F = ma Exam A — Question 24

A mass m is connected to one end of a zero-length spring with spring constant k. The other end of the spring is connected to a frictionless bearing mounted around a horizontal pole so that the mass can swing in a vertical circle of radius R around the pole. The setup is shown in the figure below. What is the vertical distance h between the center of the circular orbit and the axis of the pole? Assume that both the diameter of the pole and the rest length of the spring are negligible compared to R. h p mgR/k p (B) R (R + mg/k)/(R − mg/k)
Source: Question 24, 2020 F = ma Exam A, © 2020 American Association of Physics Teachers (AAPT) and the U.S. Physics Team. Adapted by PhysicsTrainer: reformatted into a separate question and answer choices for online multiple-choice practice; any shared setup from nearby questions is repeated here. Not affiliated with or endorsed by AAPT or the U.S. Physics Team.